Load transfer device



y 3, 1950 R. c YEOMAN ,50 8

LOAD TRANSFER DEVICE Filed Feb. 25, 1945 2 Sheets-Sheet 1 I f I I May23, 1950 R. c. YEOMAN 2,509,180

LOAD TRANSFER DEVICE Filed Feb. 23. 1945- 2 Sheets-Sheet 2 in propervertical alignment and so that the edge portions of the slabs adjacentthe joints will not readily break under load. Upon changes intemperature causing expansion or contraction of the slabs, the jointswill tend to move together or to separate. This will cause theprojecting portions l8 to slide over the bearing shoulders I withoutinterrupting the transmission of load between the slabs. In the eventthe slabs should tend to separate to an undesired extent, the crossbarportions l9 engage the shoulders I! formed by the openings IE torestrict relative movement of the slabs to such an extent that thesealing material i2 would lose contact with the slab faces. Thisconstruction prevents excessive movement of the slabs which might causethe joints to open up excessively and serves to minimize dragging of anyone slab an excessive amount on the subgrade in the event all of thejoints should not function properly. The expansion and contraction is,therefore, distributed more or less uniformly throughout the entirestructure and the expansion filler between all of the joints ismaintained under corking pressure.

In the construction illustrated in Figure 4 the load transfer membersinclude body portions 22 adapted to be anchored in the slabs in the samemanner as the body portions l3 of Figures 1 to 3. Angularly projectingroughened arms 23 project from the body portions 22 to assist inanchoring them in the slabs. Each member has one face of its bodyportion cut away as indicated at 24 to form a recess bounded on one sideby a horizontal shoulder 25 and is formed adjacent the end of the recesswith a transverse opening 26 extending horizontally through the bodyportion.

Each member is formed with a bridging portion 21 substantially half thethickness of its body portion adapted to fit into the recess 24 on theopposite member with its upper edge resting against the shoulder 25 totransmit vertical loads between the slabs At its outer end, each of thebridging portions is formed with a laterally extending head 28 adaptedto enter the opening 26 of the opposite member and to fit looselytherein.

The load transfer members of Figure 4 are adapted to be assembled in theslabs in substantially the same manner as illustrated in Figures 1 and 2with the bridging portion 21' of each member resting against theshoulder 25 of the other member and with the head part 28 of each memberfitting loosely into the opening 26 in the other member. As shown, theopenings 26 are vertically elongated so that the head parts 28 can movevertically therein. This construction operates substantially like thatof Figures 1 to 3, the head parts 28 moving in the openings to providefor limited horizontal movement between the slabs.

The construction of Figure 5 is similar to that of Figure 4 and includesa pair of members each having a body or anchor portion 3| adapted to beanchored in the slabs by angularly projecting arms 32 Each body isformed with relatively deep recess bounded by horizontal shoulders 33and has a horizontal opening 34 extending partially through the bodyportion at the inner end of the recess Bridging portions 35substantially half the width of the body portions project therefrom toenter the recesses in the opposite members with the upper and lowersurfaces thereof slidably engaging the bearing shoulder 33 and clearingcompanion shoulder 33a, The outer end of each bridging portion is turnedover as indicated at 36 to enter the opening 34 of the opposite member.The turned parts 36 are preferably smaller than the openings 3A toprovide for limited horizontal movement. In operation, the device shownin Figure 5 functions in substantially the same manher as the device ofFigures 1 to 4 to transmit vertical loads between the slabs and to limitrelative horizontal movement of the slabs.

While several embodiments of the invention have been shown and describedin detail, it will be understood that these are illustrative only andare not intended as a definition of the scope of the invention,reference being had for this purpose to the appended claims.

What is claimed is:

1. A load transfer device adapted to be im bedded in adjoining concreteslabs for transferring loads therebetween and for limiting separationthereof comprising a pair of identical integral members, each memberincluding an anchor portion adapted to be imbedded in one of the slabsand a longitudinal bridging portion extending into the anchor portion ofthe other member and adapted to span the joint between the slabs, theanchor portion of each member being formed with a longitudinal recesslongitudinally slidably to receive the longitudinal bridging portion ofthe other member and adapted to transfer vertical loads between theadjacent slabs and having an opening extending transversely from therecess, and a transversely projecting part on each of the bridgingportions entering the opening in the other member, the longitudinaldimension of the transversely projecting parts being substantially lessthan the longitudinal dimension of the transversely extending openingsfor providing limited longitudinal relative movement of the pair ofmembers and adapted to provide limited separation of the adjacent slabs.

2. A load transfer device adapted to be imbedded in adjoining concreteslabs for transferring loads therebetween and for limiting separationthereof comprising a pair of identical integral members, each memberincluding an anchor portion adapted to be imbedded in one of the slabsand a longitudinal bridging portion extending into the anchor portion ofthe other member and adapted to span the joint between the slabs, theanchor portion of each member being formed with a longitudinal recesslongitudinally slidably to receive the longitudinal bridging portion ofthe other member and adapted to transfer vertical loads between theadjacent slabs and having an opening extending transversely from therecess, and a transversely projecting part on each of the bridgingportions entering the opening in the other member, the longitudinaldimension of the transversely projecting parts being substantially lessthan the longitudinal dimension of the transversely extending openingsfor providing limited longitudinal relative movement of the pair ofmembers and adapted to provide limited separation of the adjacent slabsand a seal for the transversely extending openings adapted to preventconcrete from entering the same.

3. A load transfer device adapted to be imbedded in adjoining concreteslabs for transferring loads therebetween and for limiting separationthereof comprising a pair of identical integral members, each memberincluding an anchor portion adapted to be imbedded in one of the slabsand a longitudinal bridging portion extending into the anchor portion ofthe other member and adapted to span the joint between the slabs, theanchor portion of each member being formed with a longitudinallyarranged T-shaped recess, and a cross Dart at the end of each of thebridging portions, the bridging portion of each member longitudinallyslibably fitting into the recess of the other member and adapted totransfer Vertical loads between the adjacent slabs, and the longitudinaldimensions of the cross parts being substantially less than thelongitudinal dimension of the T-shaped recesses for providing limitedlongitudinal relative movement of the pair of members and adapted toprovide for limited separation of the adjacent slabs.

4. A load transfer device adapted to be imbedded in adjoining concreteslabs for transferring loads therebetween and for limiting separationthereof comprising a pair of identical integral members, each memberincluding an anchor portion adapted to be imbedded in one of the slabsand a longitudinal bridging portion extending into the anchor portion ofthe other member and adapted to span the joint between the slabs, theanchor portion of each member being formed with a longitudinal recesslongitudinally slidably to receive the longitudinal bridging portion ofthe other member and adapted to transfer vertical loads between theadjacent slabs and having a single opening extending transversely fromthe recess, and a single transversely projecting part on the end of eachof the bridging portions entering the opening in the other member, thelongitudinal dimension of the transversely projecting parts beingsubstantially less than the longitudinal dimension of the transverselyextending openings for providing limited longitudinal relative movementof the pair of members and adapted to provide limited separation of theadjacent slabs.

5. In combination with a pair of adjoining concrete slabs, aloadtransfer device imbedded in the adjoining slabs and comprising a pair ofidentical integral members, each including an anchor portion imbedded inone of the slabs and a longitudinal bridging portion spanning the jointbetween the adjacent slabs and extending into the anchor portion of theother member, the anchor portion of each member being provided with alongitudinal recess longitudinally slidably to receive thelongitudinally bridging portion of the other member for transferringvertical loads between the adjacent slabs and having an openingextending transversely from the recess, and a transversely extendingpart on each of the bridging portions entering the opening in the othermember, the longitudinal dimension of the transversely projecting partsbeing substantially less than the longitudinal dimension of thetransversely extending openings for providing limited longitudinalrelative movement of the pair of members and limited longitudinalseparation of the adjacent slabs.

6. In combination with a pair of adjoining concrete slabs, a loadtransfer device imbedded in the adjoining slabs and comprising a pair ofidentical integral members, each including an anchor portion imbedded inone of the slabs and a longitudinal bridging portion spanning the jointbetween the adjacent slabs and extending into the anchor portion of theother member, the anchor portion of each member being provided with alongitudinal recess longitudinally slidably to receive the longitudinalbridging portion of the other member for transferring vertical loadsbetween the adjacent slabs and having an opening extending transverselyfrom the recess, and a transversely extending part on each of thebridging portions entering the opening in the other member, thelongitudinal dimension of the transversely projecting parts beingsubstantially less than the longitudinal dimension of the transverselyextending openings for providing limited longitudinal relative movementof the pair of members and limited longitudinal separation of theadjacent slabs, and a seal for the transversely extending openings forpreventing concrete from entering the same.

RAY CYRUS YEOMAN.

REFERENQDES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,063,749 Parker Dec. 8, 19362,098,292 Jacobson Nov. 9, 1937 2,261,602 Yeoman Nov. 4, 1941 2,351,255Fischer June 13, 1944 2,355,771 Yeoman Aug. 15, 1944 2,358,328 HeltzelSept, 19, 1944

